The present invention relates to a machine for producing spun yarn and, more particularly, to such a machine having a plurality of work stations at which yarn is wound on spindles collectively driven by an endless belt.
In one known spindle drive arrangement, one or more rows of spindles are driven by a single endless belt which is itself driven by a plurality of individual drive motors distributed in positions along the length of the belt. An arrangement of this type allows significantly thinner and smaller endless belts to be used, thus leading to considerably more efficient drive transmission, as compared to an arrangement having a single drive motor for driving a larger endless belt.
In one known arrangement for driving an endless belt of a spinning machine, a drive roller is positioned in the vicinity of one of the guide rollers between the spindle rows and around which the endless belt is trained as it passes between the drive roller and an opposed clamping roller (WO 84/02932). However, this arrangement increases the risk of rupture problems.
It is also known to arrange individual drive motors between the rows of spindles and to transfer the drive forces of these motors by means of transmission belts to drive rollers which engage the endless belt (DE-OS 35 00 322). However, this arrangement requires specially designed transmission belts and clamping rollers for the endless belt, and the clamping rollers can cause detrimental compression effects on the belt.